Preview has become unusable for me over the last week. Preview froze when trying to open a pdf and I forced it to quit. Now, every time I open preview it uses all available RAM and freezes. I've tried shift clicking to open preview "fresh", but this didn't solve the problem. I've tried restoring preview from a previous time machine backup before the problem started, but this didn't help either. I'm guessing that preview settings (like which documents to open at start up) are stored outside of the preview.app container. Where are the system files for preview stored outside of the preview.app container? I'm hoping I can restore these files from a previous time machine backup. Alternatively, any other method of restoring preview would be much appreciated.